Sustainability measures are set to be implemented in a park to help stem the growth of a harmful weed.

The spread of Pennywort in five lakes in Wanstead Park over the last three years has now become so bad it has prevented the lakes from flowing into one another.

Previous attempts to clear the plant in the Grade II listed park have proved unsuccessful.

Pennywort is an invasive weed and has killed many fish and marine life in the park's ponds since it first arrived on the banks on mass.

It has also caused many bird species to leave the area.

Dwight Wood, 58, chairman of the Friends of Wanstead Parklands group for the past three years, said: "Pennywort ruins the appearance of the park and causes a general imbalance of the ecosystem.

"It's harder for us because this type of plant is new to the park and the United Kingdom.

"If we just leave this it will become a big problem.

"Unfortunately the spreading is inevitable but we are doing our best to manage the issue.

"It's frustrating for the Friends group too because we have to use resources that could easily be used elsewhere to improve and maintain the park."

Now City of London Corporation has promised to maintain the lakes and control the spread of the weed using contractors next year.

Head of Operations at Epping Forest, Geoff Sinclair, said: “Manual removal of Pennywort has been undertaken each year for at least the last three years by local volunteers.

“Sadly, despite the considerable efforts of the volunteers, this has proved insufficient to control the Pennywort and we have to consider other approaches.

He added: “As a precursor to contractor led control works in 2016 we will be undertaking a winter programme to open up the pond edges around the Perch Pond.

“In 2016 specialist contractors will be engaged to manually remove the pennywort and then to undertake targeted herbicide applications on it.”